Megapixels are nice, but sometimes what matters most in a smartphone camera is how fast you can open the camera app. Six of today’s top smartphones are put to the test.

One should not measure a smartphone camera by megapixels alone.

To stand out in a crowded smartphone market, device makers boast about having more megapixels, more filters, more zoom, more sensors. But when your baby is taking his or her first steps, what counts is how fast you can get from pocket to picture.

Google’s latest darling, the Motorola Moto X, has a trick for getting to the camera fast: twist your wrist twice and the camera turns on. No swiping icons, typing passwords, or fiddling with power buttons.

Motorola claims you’ll “never miss a shot” with its method. But how much faster is its camera wake-up shortcut compared with those of other smartphones?